Search for dissertations about: "Temperature changes"

Showing result 1 - 5 of 1142 swedish dissertations containing the words Temperature changes.

  2. 1. Climate-induced changes : Its effects on plankton food webs from the Baltic Sea

    Author : Claudia Romero-Oliva; Edna Graneli; Linnéuniversitetet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Climate-induced changes; temperature; acidification; marine food web; natural plankton community; spring; summer; Baltic Sea; Marine ecology; Marin ekologi; Akvatisk ekologi; Aquatic Ecology;

    Abstract : The Earth’s climate is determined different processes occurring in the atmosphere, land and ocean.Anthropogenic activities (mainly combustion of fossil fuels) have increased since the 1950’s, andthus the concentration of greenhouse gases that are warming up the planet. READ MORE

  4. 2. Vegetation changes on Swedish mires : Effects of raised temperature and increased nitrogen and sulphur influx

    Author : Urban Gunnarsson; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Developmental biology; Acidification; growth; long-term studies; mires; nitrogen; species richness; Sphagnum; succession; sulphur; temperature; Utvecklingsbiologi; Developmental biology; Utvecklingsbiologi; ekologisk botanik; Ecological Botany;

    Abstract : Since the start of the industrialisation, the deposition of nitrogen and sulphur and the atmospheric concentrations of greenhouse gases have increased. The main objectives of this study were to find how these changes in climate and deposition can change the vegetation of mire ecosystems and the growth of Sphagnumspecies. READ MORE

  5. 3. Bacterial and fungal growth in soil: The effect of temperature and substrate addition

    Author : Stephanie Reischke; MEMEG; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Bacterial growth; Fungal growth; Respiration; Carbon loading; Glucose mineralisation; Temperature adaptation; Temperature sensitivity; Temperature dependence;

    Abstract : Bacteria and fungi are the main agents in decomposition of soil organic matter. Their activity is determined by the availability and quality of substrate, especially its content of carbon, but also nitrogen and phosphorus. Other environmental factors, which affect the activity of the microbial community in soil, are temperature, moisture and pH. READ MORE

  6. 4. Low-temperature District Heating : Various Aspects of Fourth-generation Systems

    Author : Helge Averfalk; Sven Werner; Brian Elmegaard; Högskolan i Halmstad; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; District heating; low temperature; three-pipe systems; 4GDH-3P; District heating; low temperature; three-pipe systems; 4GDH-3P;

    Abstract : With decreasing heat demand and less availability of high-temperature heat supply in future energy systems, the current district heating systems may experience increased competition on the heat market. A viable option to mitigate increasing competition is to operate systems with lower temperature levels, and the most conceivable way to achieve lower temperature levels is to decrease return temperatures. READ MORE

  7. 5. High temperature galling : influencing parameters and mechanisms

    Author : Leonardo Pelcastre; Jens Bergström; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Maskinelement; Machine Elements; Centrumbildning - Centrum för högpresterande stål CHS ; Centre - Centre for High Performance Steel CHS ;

    Abstract : Damage of forming tools at elevated temperatures is a major problem in metal forming processes such as hot stamping. Of special importance is the occurrence of adhesion and gross material transfer from the work-piece to the tool surface, a phenomenon known as galling. READ MORE